New ICF Report Finds U.S. Has Just 3% Excess Generating Capacity as Electricity Demand Accelerates

RESTON, Va. (June 25, 2026) - ICF (NASDAQ:ICFI), a leading global solutions and technology provider, today released a new report on rising U.S. electricity demand, the available capacity to serve that growth, and the investments needed to maintain reliability and affordability.

The report, Electricity demand growth: How will the grid keep pace?, finds that the U.S. power system currently has only about 26 GW of excess generating capacity above minimum resource adequacy requirements, which is roughly 3% of total capacity.

The report also found that ERCOT and PJM, the nation's fastest-growing electricity markets, have no excess generating capacity available to reliably support additional demand growth.

Meanwhile, total U.S. electricity demand is expected to rise 21% by 2030 and 39% by 2035. Peak demand is projected to increase 14% by 2030 and 25% by 2035, with the fastest growth concentrated in regions seeing the most data center development, industrial expansion, and electrification.

The report also finds that approximately 445 GW of new generation capacity is forecast to be added between 2026 and 2030, but only 68 GW is expected to come online in 2026; and not all of that capacity will contribute equally to reliability during periods of peak demand. As such, margins are projected to remain low through 2030, with roughly 20 GW of excess generation capacity anticipated by 2030.

The findings suggest that the next phase of U.S. electricity demand growth will be defined less by how much demand increases and more by to what extent, and how quickly, generation, transmission, and grid infrastructure can be built to meet it.

"In recent years, the conversation has focused on how much electricity demand would grow, but these findings suggest the more important question is what needs to change to allow infrastructure development to keep pace with demand," said Kyle Wiggins, ICF senior vice president for energy, environment and infrastructure. "A 3% capacity cushion leaves little room for error. Utilities, grid operators, developers, and policymakers will need to act in concert across generation, transmission, demand-side resources, and flexible operations to keep pace with demand while maintaining reliability and affordability."

ICF partners with many of the nation's leading utilities, developers, federal agencies, state energy offices, and nongovernmental organizations, providing end-to-end services across the energy value chain-from strategy and analysis to implementation and customer engagement. The company currently delivers hundreds of active demand-side management programs across North America.